[Coco] 6809 / General CPU question

Arthur Flexser flexser at fiu.edu
Thu Feb 24 14:45:38 EST 2011


A further interesting note is that this is a rare case where the 6809 is NOT
emulated correctly by the 6309, presumably because Motorola did not document
the $3E opcode.  In the 6309, it gets vectored to the 'illegal opcode'
address.

Art
On Thu, Feb 24, 2011 at 1:02 PM, <jdaggett at gate.net> wrote:

> Interesting note is the 6809 has a restart opcode. Issuing an opcode of $3E
> will will force the processor to load the RESET vector and start execution
> again.
>
> hope this helps
>
> james
>



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